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1.
V. N. Mughnetsyan A. A. Kirakosyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2008,43(4):173-176
The effect of interdiffusion of aluminum and indium atoms on the exciton emission energy and binding energy in InxGa1?xAs/AlyGa1?yAs quantum dots is studied. It is shown that the emission energy increases monotonically with increasing diffusion length, while the binding energy has a maximum. 相似文献
2.
V. N. Mughnetsyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2007,42(5):195-200
The effect of a uniform longitudinal magnetic field on the binding energy and photoionization cross-section of a hydrogen-like donor impurity is studied for a semiconductor quantum well-wire approximated by a cylindrical well of finite depth. The selection rules and analytical expressions for the photoionization cross-section are obtained depending on the magnetic field induction, impurity position, and light wave polarization. 相似文献
3.
V. N. Mughnetsyan A. A. Kirakosyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2007,42(2):55-61
A new method of theoretical investigation of the interdiffusion effect on electron states in quantum dots is proposed. The
main point of the method is the replacement of the “veritable” confining potential formed due to the diffusion by a model
potential, for which the Schr?dinger equation solutions and the energy spectrum are known. In the framework of the proposed
method we calculate the positions of edges of the conduction and heavy hole bands and the absorption coefficient of interband
transitions depending on the diffusion length in spherical InxGa1−x
As/AlyGa1−y
As quantum dots, using the Wood-Saxon potential as a model one.
Original Russian Text ? V.N. Mughnetsyan, A.A. Kirakosyan, 2007, published in Izvestiya NAN Armenii, Fizika, 2007, Vol. 42,
No. 2, pp. 83–91. 相似文献
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The effect of uniform electric and magnetic fields on binding energy and photoionization cross-section of an off-axis hydrogen-like donor impurity in a QWW, approximated by a cylindrical well of finite depth, is investigated within the framework of variational approach. The dependencies of the binding energy and photoionization cross-section on electric field strength, magnetic field induction, wire radius and impurity position are obtained. The cases when the polarization vector of incident radiation is parallel and perpendicular to the wire axis are both discussed. 相似文献
6.
Nahar Singh VN Ojha Nijhuma Kayal Tarushee Ahuja Prabhat K Gupta 《Chemistry Central journal》2011,5(1):17
Arsenic is the toxic element, which creates several problems in human being specially when inhaled through air. So the accurate
and precise measurement of arsenic in suspended particulate matter (SPM) is of prime importance as it gives information about
the level of toxicity in the environment, and preventive measures could be taken in the effective areas. Quality assurance
is equally important in the measurement of arsenic in SPM samples before making any decision. The quality and reliability
of the data of such volatile elements depends upon the measurement of uncertainty of each step involved from sampling to analysis.
The analytical results quantifying uncertainty gives a measure of the confidence level of the concerned laboratory. So the
main objective of this study was to determine arsenic content in SPM samples with uncertainty budget and to find out various
potential sources of uncertainty, which affects the results. Keeping these facts, we have selected seven diverse sites of
Delhi (National Capital of India) for quantification of arsenic content in SPM samples with uncertainty budget following sampling
by HVS to analysis by Atomic Absorption Spectrometer-Hydride Generator (AAS-HG). In the measurement of arsenic in SPM samples
so many steps are involved from sampling to final result and we have considered various potential sources of uncertainties.
The calculation of uncertainty is based on ISO/IEC17025: 2005 document and EURACHEM guideline. It has been found that the
final results mostly depend on the uncertainty in measurement mainly due to repeatability, final volume prepared for analysis,
weighing balance and sampling by HVS. After the analysis of data of seven diverse sites of Delhi, it has been concluded that
during the period from 31st Jan. 2008 to 7th Feb. 2008 the arsenic concentration varies from 1.44 ± 0.25 to 5.58 ± 0.55 ng/m3 with 95% confidence level (k = 2). 相似文献
7.
V. N. Mughnetsyan A. A. Kirakosyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2009,44(3):140-144
The effect of interdiffusion of Al and Ga atoms on the confining potential and band structure of a three-dimensional superlattice, composed of initially spherical GaAs/Ga1?xAlxAs quantum dots, is investigated in the framework of the modified Wood-Saxon potential model. It is shown that the interdiffusion leads to the disappearance of the quantum dots’ spherical symmetry and to the broadening of the superlattice energy minibands. 相似文献
8.
The technology of obtaining ceramic Bi-Pb-Sr-Ca-Cu-Fe-O HTSC with reproduced properties of a Josephson medium is elaborated. The possibility of creation of the magnetometer with a sensitive element on HTSC ceramics is considered, using a sensitive method of contactless measurements based on the tunnel-diode self-generator. The steepness of the frequency-field behavior is determined, which is one of the main parameters determining the possibility of the HTSC sample’s application in magnetometers, as well as the value of the critical field of hypervortices penetration. 相似文献
9.
Vram Mughnetsyan Vidar Gudmundsson Nzar Rauf Abdullah Chi-Shung Tang Valeriu Moldoveanu Andrei Manolescu 《Annalen der Physik》2024,536(4):2300274
Quantum electrodynamical density functional theory is applied to obtain the electronic density, spin polarization, as well as orbital and spin magnetizations of square periodic arrays of quantum dots or antidots subjected to the influence of a far-infrared cavity photon field. A gradient-based exchange-correlation functional adapted to a 2D electron gas in a transverse homogeneous magnetic field is used in the theoretical framework and calculations. The obtained results predict a non-trivial effect of the cavity field on the electron distribution in the unit cell of the superlattice, as well as on the orbital and spin magnetizations. The number of electrons per unit cell of the superlattice is shown to play a crucial role in the modification of the magnetization via the electron–photon coupling. The calculations show that cavity photons strengthen the diamagnetic effect in the quantum dot structure, while they weaken the paramagnetic effect in the antidot structure. As the number of electrons per unit cell of the lattice increases, the electron–photon interaction reduces the exchange forces that will otherwise promote strong spin splitting for both the dot and the antidot arrays. 相似文献
10.
V. N. Mughnetsyan M. G. Barseghyan A. A. Kirakosyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2007,42(6):287-291
The effect of a longitudinal magnetic and a transverse electric fields on the binding energy of a hydrogen-like donor impurity is studied for a semiconductor quantum well-wire approximated by a cylindrical well of finite depth. It is shown that the magnetic and electric fields as well as the impurity distance from the wire axis are the effective tools for the influence on the binding energy. 相似文献